Preface
This guide is targeted to the A202KC/A203KC and 902KC/903KC with mentions of info for the KY-42C.
It’s mostly a collection of random bits of information I had to research or figure out. And some tips for power users to make the phone more viable for daily use.
If you are new to Japanese flip phones, then know that these phones are a hassle to get set up, and are not really made to work outside of Japan. These two phone models generally work in NA and some parts of Europe from what I can see but you will need to do your own research on if they will work for you, and even if they do work there is a non-zero chance they won’t work outside of cities in specific countries, or in other cities. I’ve also heard that in Australia a lot of Keitai’s are blacklisted, but the 902KC seems to work fine.
For context, the A202KC is the successor to the 902KC. The 902KC is well documented and tested online, I do not own the 902KC but have used posts on the phone for the A202KC since they are virtually the same minus a few differences.
This will include info for Features, Troubleshooting, Customization, Rooting, and any other tidbits that I hope will be useful to someone. I will attempt to keep this post updated with any new relevant info, if you have anything to share and add to this post please leave a comment :).
I’ll also try to link any guides or comments I found useful throughout this guide.
Versions
902KC / 903KC / 904KC / A202KC / A203KC / A204KC
For context, the 902KC/903KC are the exact same phone but simply with different providers. 902KC is from Softbanks and the 903KC is from Y!Mobile. This is the same situation for the A202KC/A203KC.
As far as I am aware the only difference is going to be what provider shows up when you boot up the phone, but there are rumors that the software on the 903KC is better built to handle international bands (source). However the band compatibility is the same on both providers websites.
Because of this annoying naming scheme I’ll just be referring to them as 90XKC/A20XKC.
There is a 904KC that seems to be a camera-less version for businesses. I have also seen sites that mention a A204KC, I assume this to be largely the same situation as the 904KC.
KY-42C
This phone is less well documented on the sub but is very alike to the A20XKC. The phone has different bands then these two phones and I have heard that the compatibility is good for parts of the U.S. It also features an upgraded CPU that can be rooted like the A20XKC (and runs Android 10!).
The bands are on the provided spec page below but in case you can’t access it the 4G bands are: (1, 3, 5, 12)
Specs (Requires a VPN connection to Japan)
Blog post from Wiggle on the KY-42C
Differences
Here’s links to the specs for both phones:
A20XKC
90XKC
I’d recommend checking out this post from Snoo-98535, they go into depth having had both phones but I’ll give you a rundown here as well.
Android:
90XKC runs android 8.1 while the A20XKC runs android 10. This helps a lot with app compatibility, and I have yet to have any significant issues on the A20XKC in terms of apps. I have seen people having issues due to the android version on the 90XKC however. They also both operate on Android go.
CPU Speed:
From what I have heard the A20XKC feels much faster then the 90XKC.
Rooting: Because of the new CPU chip you can root the A20XKC with MTKclient. There is currently no publicly known way to root the 90XKC, however it (allegedly) has been done..
Hardware: A20XKC loses the flashlight and pedometer.
Storage:
The A20XKC will have less internal storage due to a larger system. Both phones have only 8 GB of built in storage, 90XKC uses 2.7 GB while A20XKC uses 4.4 GB. I am getting by fine with this storage restriction however, especially with making use of my SD card heavily.
Network/Bands
If you are not familiar already with bands it’s incredibly important that you look into them before buying a Keitai. These phones are made only to work in Japan with international compatibility being an afterthought. If you don’t look into it and just buy the phone there is a very real possibility that it will not work at all. And of course you need to make sure that the phone is sim unlocked. For an approachable introduction I recommend this guide (This section is mostly taken from that guide).
Band compatibility
(The far right column is international band support, the circle means it supports that frequency. LTE = 4G)
A selling point from Kyocera on the A20XKC is that it has more band compatibility, but comparing these side by side the only difference is that the A20XKC now has access to Band V in the 3G spectrum.
To check if the phones bands are compatible with where you live use this website: https://www.cellmapper.net/map
You can check various providers and the bands that they support. Specifically you will need to make sure it works on the 4G bands. Consider also where you may travel to and if you would get signal there. If you cannot find your provider it is likely because it is a MVNO, look up which infrastructure they operate on and plug that into Cellmapper.
You should aim for at least 2 compatible bands in your area. I would also advise against bothering with contacting your provider about these phones as they usually will just tell you to get a new phone.
APN Settings
In order to get 4G you are going to need to manually input your providers APN settings. To do this search “(Provider) APN Settings”. Your provider will have a website with the APN settings for you to input into the phone (look for “Access Point Names”). I really recommend you use screen mirroring for this. After entering this restart your phone.
Troubleshooting
There are various carrier specific issues with this phone, and if you have issues with it you can try looking up your carrier on the dumbphones subreddit to see if anyone’s been having similar issues on these phones.
Threads on carrier specific issues:
T-Mobile
Mint
There also seems to be weird specific sim card issues, mentioned in this post.
If you have 4G but are having trouble with VoLTE (Voice over LTE) and mms:
Input a new APN separately from the one earlier and set it as this:
Names: ims
APN: ims
APN Type: ims
And make sure that you keep your carrier APN selected. And restart.
I found that mine only registered after setting APN protocol and APN roaming protocol as IPv4/IPv6 in both the ims APN and my carriers APN.
On the 90XKC it seems possible to access a hidden cellular testing menu with a shortcut maker that will allow you to force LTE bands. In this post they mention that it helped them to force VoLTE to enable. I couldn’t get any similar menu on my A202KC however.
If you are having trouble using data here are some troubleshooting steps for you to try out:
Turn off GSM, select 3G/4G instead.
What worked for me strangely was that I re-flashed my phone. Maybe it just kicked it into working, or maybe debloating specific software before setting up your APN’s can mess with registration and such. You can also just try factory resetting if you want to give it a shot.
Buying
The A20XKC and 90XKC are not sold outside of Japan by Kyocera or any carriers.
Regardless of where you buy the phone, you will need to make sure that it is Sim Unlocked, or “Sim-Free” as it is sometimes translated. If somehow you end up with a Sim Locked phone, check the troubleshooting section.
To get one of these phones the options are either a reseller that ships to your country or buying used on the secondhand market. For the used market you can go on second hand markets like Ebay and find a variety of reputable sellers there. There is also the option of Japanese auction sites like Zenmarket. You can find mentions of Japanese auction sites to check in the dumbphones subreddit.
Guide for stores in Japan A post on Proxy delivery services
Getting Started
This section will go over setting up the phone and tools you can use for modification.
For a quick rundown of the default keyboard, the button with a cassette is the back button. The hang up button (with a power icon) hangs up the phone, terminates whatever app you are in, and shuts down the phone when held. To type a space with the default keyboard use the D-Pad right key. The bottom right custom key can be held for the cursor, and the II custom key can be held to pull up the notification panel.
The phones do not come with any way to install apps natively so we will need to side-load them in order to install them. We can install an app store onto it though and install apps from the device once set up.
First we will need to set up ADB (Android Debug Bridge) which will allow us to connect the phone to a computer and install apps.
Go into Settings>About Phone, in here click Build Number 5 times (It will say “You are now a Developer!”). We will now have access to Developer options which will be in Settings>More Settings>Dev Options. In here find USB Debugging and enable it. Now we can make use of ADB and Vysor/Scrcpy.
Download ADB here.
Download USB Drivers here
For this version of ADB, extract it and run ADB. Throw your apk files into the folder and in ADB type:
adb install (name of your apk).apk
You can rename the apk to make this easier as well.
Once downloaded just plug the phone into your PC (Make sure your cable supports data transfer) and press allow on the phone. If the option comes up make sure to press “always allow” so that you can have an easier time if you have an issue such as getting locked out. Now we can use ADB to install apps onto the phone. To make things easier I’d recommend using a screen mirroring software for the next parts.
Options I’d recommend for screen mirroring are Vysor or Scrcpy for this, both work on Windows, Linux, and Mac. Vysor is plug and play and just works. Scrcpy is slightly more of a hassle to use but is open source and much faster (plus no paywalled features).
I’d recommend installing F-Droid (For FOSS apps) and Aurora Store (For everything else). Alternatively you can just download the apps you want individually online and just side load them through ADB, this will save on file space but these app stores also make updating simpler.
For sake of mind there are a few apps that I recommend you install immediately.
TT9
TT9 is highly suggested across the dumbphones subreddit due to these phones using multi-tap natively. For multi-tap you tap the key to cycle through letters. Newer flip phones adopted T9 which is a predictive text system. It allows you to just need to press once for each letter by pressing the corresponding key and it predicting the word based on the letter arrangement possibilities. You can cycle through the options and it will remember which words you use most for better prediction. It can learn your word preferences, and you can add your own words and slang into the dictionary. You can get very fast with this.
Make sure to enable alternative scrolling method if you plan on using the lock screen with TT9 or you will be locked out of the device. On my phone this is in the Appearance settings but it may be elsewhere depending on your version. If you do get locked out because of this, check the troubleshooting section.
You can tap “1” to access punctuation, and you may tap “0” for a space or scroll for various symbols, double space for period. You can hold the number keys down to input a number in letter modes. Punctuation is considered in predictions as well so you do not need to manually insert an asterisk, just press the punctuation key it will figure it out.
I recommend reserving a key for swapping input modes, it will make your life a lot easier. As sometimes you will need to swap to Multi-tap to type a word manually. I also recommend having a button bound to add words to the dictionary, it will save you the hassle in the future. Bind a key to backspace, as the built in backspace does not play nice usually and can kick you out of apps while typing.
These are my settings for key-binds in TT9:
- Call button for scrolling through input modes
- Asterisk for Shift/Capitalize
- Hold Asterisk for adding a word
- Hashtag for backspace
KeyMapper
KeyMapper will allow you to change the functions of your buttons, which will allow you to make it a lot easier to use.
When creating a key map you can overwrite any functions already bound to the button, or you can keep the function by enabling “Do not remap” for the key bind in its setting.
You can have have functions bound to single press, double press, and long press. (Or even sequences)
There are no physical brightness or volume controls, and for sake of mind you really should bind them somewhere.
Keymapper also has folders, which you can assign to app constraints to create app specific profiles. For example on my phone I have the a universal profile for functions, and specific profiles for each app. You can bind keymaps to press a certain part of the screen, so you can bind them to in app functions. I’ve managed to simplify most of my navigation on the phone to eliminate the need for a cursor in apps I use often.
Never set KeyMapper as the default keyboard if you use a lockscreen it will lock you out. If you want to have Keymapper bind buttons to keyboard inputs use key codes (Requires Shuzuku/Sui)[https://github.com/RikkaApps/Sui/].
Note: Unfortunately Keymapper does not work while the phone is closed, as the phone enters a kind of sleep mode. If this was not the case I would love to be able to control music all with the side button, but it only works to disable or enable manner mode. I end up just having to flip it open and pressing skip and closing it again. Thankfully Bluetooth controls for skipping, pausing, and volume control still work like a charm. I am curious whether inline remotes would work with the right setup as well.
C9
C9 is a custom cursor app that I heavily prefer to the built in cursor.
The default cursor can select, scroll by moving the cursor to the bottom or top of the screen (not the sides I’m pretty sure), and when holding down select it will enter a scroll mode to scroll the page with the D-Pad. However with this cursor you are unable to press and hold (which causes you to need to swap to the D-Pad to do so and then back to the cursor again).
C9 separates the scrolling and mouse movement by allowing you to use the numpad to scroll with swipes in any direction, as well as having dedicated buttons for zooming in or out through gestures. The mouse speed can be customized with acceleration, and you can enable an option to have the mouse go past the edge to the other side of the screen. Also it fixes my main grievance with the original cursor which is that it cannot be used to select, hold, and drag. I cannot stress how much easier this cursor makes navigating literally anything compared to the default, I’ve even been able to use it to access previously inaccessible functions. You can even bind it in Keymapper and overwrite the stock cursor button, and have it tap to toggle instead of hold.
(It also lets you use a custom image or gif for the cursor)
The Dev is actively maintaining and improving the app and has directly addressed some of the issues I have faced with it on the phone. Highly recommend!
Apps/Debloating
Apps
For apps I personally strive to use open source ones to avoid bloatware and to maintain privacy. This will keep file size down and allow the most flexibility.
Texting:
If you are on the 90XKC: I highly recommend using QUIK SMS. It’s lightweight and simple with a great UI.
If you are on the A20XKC: There is a very strange issue with the phone receiving SMS on any app other than Google Messages and the default texting app. This issue is strangely linked to the A20XKC CPU itself. The result of this issue is that when the app is killed or force closed the phone will literally delete the SMS.
This issue will only occur if the phone is under strain and kills background apps, or if you close the app with the power button instead of exiting with the back button. Although if you do not wish to deal with the issue at all then I recommend using google messages or the default.
For power users, there is a work around but it requires rooting the device. In my other post I have a section on this workaround.
Github issue thread
Post on r/garahho
WhatsApp and Signal work great on the phone, although I can’t seem to be able to direct them on where to store images which has been bloating my storage.
Phone/Contacts:
For FOSS dialer apps I’ve found they all have issues with the numpad when using TT9. The stock dialer also has the feature of hanging up when you close the phone, I don’t believe third party dialers feature this or can implement this.
For contacts I recommend Fossify Contacts. It does seem to have an odd issue with not sharing contacts with sms apps however, I have a workaround in the troubleshooting section later on. There is also Connect You which is more feature rich, but is more difficult to navigate on the phone.
Music:
People have had moderate success with using Spotify Lite on this phone, although it takes up a lot of space.
I’d recommend using a music player app with your own downloaded music in the SD card. There are likely plenty of decent ones on F-Droid.
I personally use PowerAmp (This app has a one time purchase to activate). It’s open source, supports my SD card, and has great customization.
In a lot of countries ripping CD’s and using the files is legal, and you can buy digital high fidelity music files online from various websites.
Browsers:
Fennec works alright and is less bloated than most. Browsing on this phone is not a great experience regardless though and tends to crash often for me. Doing anything other than basic web surfing is not very easy at all.
Debloating
Thread on apps to remove https://www.reddit.com/r/dumbphones/comments/183mq2l/debloating/_question/_kyocera/_902kc903kc/
Without root UAD can’t actually uninstall system apps but effectively disables them instead. This will not save on space but it will help make the phone faster by stopping useless background services. This is a good thing in most cases since you literally can’t brick the device because of that. System apps will simply be re-enabled after a factory reset.
UAD can be installed from this source.
Do not uninstall jp.co.omronsoft.iwnnime.ml, this is in the recommended section of UAD but it is the default keyboard and removing it while not having TT9 installed will lock you out.
For a list of bloat check the linked threads, I will also be trying to (eventually) add these and some I have found to the new UAD fork.
Customisation
Launchers
Tip, disable/debloat the stock launcher and it will stop prompting you to select the launcher every time you restart.
Stock: The stock launcher is very comfortable to use if you get used to it, and it has specific button functions natively built in that just work. Also, consider the fact that downloading another launcher will take up more space. OperatorSlayer
Niagara: This is the one I use in the image posted with this.
Nova: milo_1982
Microsoft Launcher: lovetama_5522
olauncher: lilian0030
Dark mode
Dark mode is hidden in the original android settings app, it can be accessed using something like Activity Manager. Just look for General settings and launch from there. You can also turn on auto rotate, but I believe this is a feature that only works on the 90XKC.
If activity manager does not work on the 90XKC you can use QuickShortcutMaker, which seems to work for some.
Here is a guide to do this on the 90XKC with screen mirroring
You can also force it open using ADB
Misc
Phone charms can be added by taking off the back, sliding in the charm string, and pulling it over the plastic nob.
Hiding Status Bar: Some launcher have functions to hide the status bar on the home screen. You can use ADB to disable it using this method.
I recommend using overscan to hide the nav bar, the above method removes it completely. Overscan simply moves the nav bar off screen instead.. Keep in mind this will hide the functions labelled in the nav bar, but you can learn them since they’ll still be functional.
Misc/Tips
Audio
Bluetooth on these phones just work. It supports the Bluetooth controls flawlessly even when the phone is closed. I have the Sennheiser Momentum 4 headphones and can switch songs, change volume, and modify my noise cancelling perfectly fine.
The USB C port can be used for audio but it will only work for some cables. The port only supports audio through something called passthrough, which basically just means it only supports USB C cable with no DAC (Digital Analog Converter). This is the same for the Moto Z, and Motorola makes a cable for their phone to address this. Most cables won’t mention passthrough, but the biggest thing to keep a lookout for is whether they advertise it having a DAC or not. You can also take a look to see if they mention that they specifically support the Moto Z or another phone with this same requirement.
Charging Cradle
Thanks to salyrus for this info
There is a charging cradle that works for both of these phones. The cradle is made for the KY-41B but is the same dimensions so it works for these phones as well, This cradle only comes in white and is strictly for charging.
Batteries
A202KC: KYBEZ1 Ky-42C: KY01 902KC: KYBAQ1
Could not tell you if these are cross compatible. They also should be the same per model but if buying the a203kc/903kc batteries double check their manuals in case. Also shipping the batteries from Japan seems to be impossible.
Sub Display Date Tweak
If you go to the sub display settings and put it to small it will add the date to the display.
Updating
These phones update using OTA (Over the air). You cannot update them outside of Japan. I’ve tried a VPN and had no luck with that either. Also you may need to have an active usim from Softbank/Y!mobile in order to receive the updates even if you were in japan. I do not know much about how that works however and it seems to contradict information from Softbanks update page.
Troubleshooting
SIM Locked
If you forgot to check if it was unlocked first, or if you got unlucky and it was mislabelled then there are ways to unlock the phone still.
Step by step guide:
- Book a flight to japan
- Speed learn Japanese on the plane
- Go to Softbank/Y!Mobile
- Ask really nicely for them to unlock it for you
- Profit
If you cannot speak Japanese, or more likely if you are as broke as I am then there is a cheaper but much sketchier option. I will link it here for you to check out but I have no experience going through the process personally and you should really research it yourself if you are faced with this issue. Although a youtuber I saw named F4mi did say that it worked for her.
I LOCKED MYSELF OUT
I actually faced this issue because I made the mistake of setting KeyMapper to the default keyboard. Thankfully, if you have your phone set to “Always allow connection” you can just plug it into the permitted computer and change the keyboard to the default or TT9.
In the terminal:
adb shell
ime set io.github.sspanak.tt9/.ime.TraditionalT9
Alternatively if you can’t use TT9 for some reason, you can reset the keyboard to the default:
adb shell
ime reset
I’m stuck in infinite bootloop hell
I haven’t faced this personally, but here are some threads with people that went through a similar issue:
If you’re on the A20XKC it could be possible to flash someone elses boot image onto your device. This would use MTKClient. If this does happen to you and you would like to try send me a dm and I can send my image files.
Opening Dev Options crashes Settings
Had this weird issue after rooting the phone and re-flashing, this thread fixed it for me.
Fossify Contacts won’t share contacts to other apps
Weird issue with this one, Fossify contacts does not make its own contacts directory, and because of that you need to make it with another app. I believe that you can do this with the stock contacts app but an easier solution for me has been installing this alternative FOSS contacts app. Just import all your contacts into it, download Fossify Contacts, and then delete the alternative contacts app. Fossify will now continue to use the new folder and share contacts to the other apps.
Resources
Digino User Guides:
Kyocera Open Sourced Builds:
http://android-dev.kyocera.co.jp/source/source.html
I have not heard of anyone successfully using these files to update the phone, and I have heard that a “Factory Signature” may be required and that the phone would not boot properly from a boot that you created